BenPerfected

We am running Holley 1150 CFM 2-circuit carbs. Assuming the BG's are similar(should be), I think on a NA application the jets should be in the mid to high 80's with PV's. The 6.5 PV's may also be opening too soon. You can find the opening point with a vacuum gauge. We set ours to open at about 80% of the WOT RPM.

BenPerfected

Here are the King Demon spec's. Your 94 jets are BG stock, but the KD's are set up w/o PV's. PV's are = to 8-10 jet sizes. I believe you are on the right path if you use the right PV, but you will have to jet down to not be in a constantly rich condition. The Holley 1150 # 7320 is also set up from Holley with 94 X 94 jets w/o PV's.

KING DEMON GENERAL COMPETITION GAS - GC
MODEL # 1090 AD 1090 STD 1190 AD
PART # 8728020GC 8728030GC 8838020GC
VENTURI SIZE: 1.720 1.720 1.812
IDLE AIR BLEEDS: .046 .046 .040
INT. AIR BLEEDS: .070 .070 .043
H.S. AIR BLEEDS: .029 .029 .028
BOOSTER TYPE: ANNULAR STRAIGHT ANNULAR
BOOSTER LEG: .169 .169 .169
SQUIRTER SIZE: 42 42 42
BUTTERFLY SIZE: 2.00 2.00 2.00
AIR HOLE SIZE: NONE NONE NONE
PUMP CAM # 643 643 643
PUMP CAM COLOR: YELLOW YELLOW YELLOW
METERING BLOCK # A-12330 A-12330 A-12330
M-BLOCK COLOR: SILVER SILVER SILVER
SIPHON BREAK: .028 .028 .028
E-HOLE POS. #1 .029 .029 .029
E-HOLE POS. #2 .029 .029 .029
E-HOLE POS. #3 .029 .029 .029
E-HOLE POS. #4 .029 .029 .029
P.V.C.R. SIZE: .059 .059 .059
I.F. RES: .029 .029 .029
T.S. TES: OPEN OPEN OPEN
INT. PICK UP: .040 .040 .040
INT. FEED RES: .046 .046 .063
MAIN JETS PRI: # 93 # 94 #96
MAIN JETS SEC: # 93 # 94 # 96
POWER VALVE PRI: PLUGGED PLUGGED PLUGGED
POWER VALVE SEC: PLUGGED PLUGGED PLUGGED
LINKAGE TYPE: PROG. PROG. PROG.
N&S SIZE/TYPE: .130-VITON .130-VITON .130-VITON
ACC. PUMP DIA. SIZE 50 CC 50 CC 50 CC

CNC

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CNC

Thank you Ben.....

Exactly the info I was looking for. I will let you know how it works. These are blower motors minus the blowers what effect would the lower compression pistons have on carburetion (jetting P/V)?

Randy

BenPerfected

Our CR is at 9.3 to 1. Not positive, but I don't think the CR will impact the jetting. Anybody? Many/most the single plane intake manifolds seem to make cylinders 1&3 and 2&4 richer than 3&5 and 4&6. We are still tweaking our jetting but currently we are still richer on the front cylinders (reading the plugs) with a 88(R) X 85(F) jet pattern + PV's. My thought is for you to consider starting your jetting here and then run 5 min at 3,000-3,500 RPM and look at your plugs while still on the water with no idle time.
The fun part about a carburetor is you can do most the work yourself and get measurable results

CNC

Getting close on jetting, 88p and 94s What power valves are you using? All I had were 88 and smaller mains, I would like to go smaller on the secondaries ...... Starboard motor quit after 10 min. I thought its was the MSD box, that was what it felt like, just quit, turned out to be coil wire and coil tower burned off???? WTF would cause that?? No one I have talked to or shown it to had an idea why.

MER Performance

Are you on the dyno or in the boat?

CNC

Boat, I bought the boat this way .... it sat 2 years. I plan on pulling and dynoing this winter

x7734x

I had the same issues with my BG King Demon. I took a carb guy with me to the lake to tune it.

Make sure your floats are not sticking. I had this issue as well.

MER Performance

See your off line.The King Demon's going to be the hardest to tune for you, Have done plenty of them on the dyno, they are lean out of the box. I have had to start with a smaller main air bleed to pull more fuel in that circuit, go to a smaller int. air bleed drill out the transfer jets that are on the metering block. This is very hard to explain, depending on the flow # on the heads and your cam specs, very hard. It takes drill bits in the
.o18" and Numbered drill index. Are the carbs boost ref. If not that PV is no good to you. If you haven't used these yet I would send them back and get the 4150 style 1025rs that carb if using two per engine will work great. It will support 1200 hp and 10 psi boost. You will be able to set that one up easier with only jet changes, they would be my first choice for your application.